PHILADELPHIA -- Jordan Holloway says the key to his historic run out of the Miami bullpen recently isn't a matter of his role -- he's simply just attacking the zone more.

Holloway became the first pitcher in franchise history to turn in a relief outing of at least five hitless innings in the Marlins' 7-0 victory in Friday's nightcap against the Phillies. That came on the heels of the right-hander allowing only two hits over 4 1/3 scoreless frames against the Dodgers on July 7 in his previous appearance.

"Just getting ahead of hitters, pounding the strike zone with all my pitches," said Holloway, who was returned to Triple-A Jacksonville on Saturday after serving as the 27th man for Friday's doubleheader. "Really, that's a game-changer. Keeping guys in swing mode, for the defense, makes it a whole lot easier to pitch."

Holloway threw 68% of his 72 pitches for strikes on Friday night. He threw 70% for strikes against the Dodgers. All told, he registered a strike percentage of 68.9% (91 of 132 pitches) in those two outings. That's a considerable jump from 58.8% (228 strikes on 388 pitches) in his first nine appearances.

The other thing those two relief appearances have in common: Each came after Ross Detwiler started the game as an opener.

With Holloway handling the bulk of the innings behind Detwiler, Holloway allowed just two hits while racking up 12 strikeouts over 9 1/3 scoreless frames.

Overall, he has turned in 20 1/3 scoreless innings in eight relief appearances this season. Opponents are hitting just .087 (6-for-69) with a .279 OPS against him when he comes out of the bullpen. Meanwhile, Holloway has a 9.31 ERA over 9 2/3 innings in his three starts, with opponents posting a .289 average and a .977 OPS in those contests.

"He has been more successful coming out of the bullpen, but in theory, it is a start; it's just not starting the game. But he has been the bulk-innings guy in those scenarios," manager Don Mattingly said. "And really, it's leading him toward starting, where he's got 90 pitches, 95 pitches, 100 pitches, where he could start a game. But he has been very successful coming in after the opener."

For Holloway, the drastic splits are just a matter of coincidence -- a premise that is certainly plausible, given the small sample size.

"I'm just going to take what I've been working on and getting better at it, whether I'm in the bullpen or in a start. Just some fine little minor fixes in the delivery to get a little more consistent and stay in the zone as much as possible," Holloway said. "Realistically, the mindset has stayed the same: Just go out and attack hitters. In the bullpen, it seems like I've been able to do it a little better, but I don't think starting or relieving has anything to do with it."

The Marlins plan to keep Holloway stretched out at Jacksonville after throwing 72 pitches on Friday, though it remains to be seen whether they opt to deploy him behind an opener or as a true starter. The opportunity for more innings figures to present itself down the stretch, especially with Pablo López landing on the injured list (right rotator cuff strain) Saturday and Miami already planning to limit the workload of some of its other young starters, like Trevor Rogers.

"He's starting to demand the ball, honestly, the way he's throwing it," Mattingly said of Holloway. "We're seeing some real strides in what he's been able to do out there. Again, it's always been stuff that you know works here [at the MLB level], it was just a matter of getting a handle on it, getting in the zone, being able to get in good counts, things like that."